The present invention relates to centrifugal pumps in general, and more particularly to improvements in means for mounting the casings of centrifugal pumps in or on foundations, base plates or analogous supports. Still more particularly, the invention relates to improvements in means for securing to a foundation or a like support a centrifugal pump whose casing is subjected to pronounced or very pronounced external stresses.
High-output centrifugal pumps are often subject to substantial external stresses which must be transmitted to the supports for the pump casings. A typical example of externally stressed centrifugal pumps is the feed pump in a nuclear power station. Such pump has a capacity in excess of 4000 m.sup.3 /h, a total head of approximately 600 m and a speed in the range of 5000 RPM. The feed pumps in fossil fuel power stations, too, are subjected to very pronounced external stresses. These pronounced stresses can interfere with proper operation of the pumps and/or pump motors. Therefore, and since the pump normally constitutes (or is supposed to constitute) a fixed component of a pipe line, it is very important to adequately anchor the pump casing in or on a support, such as a foundation or a base plate.
In many presently known pump-motor aggregates, the pump casing is secured to a foundation or to another support through the medium of specially designed projections which are integral parts of the casing (the casing is normally a casting) and are affixed to the support. As the magnitude of anticipated stresses increases, the dimensions of such extensions also increase which, in turn, increases the likelihood of defects in the respective portions of the casing. Attempts to replace extensions which are integral parts of the casing of a centrifugal pump with projections which are welded to the casing have met with little or no success. The main reason for such failure of welded projections or extensions is that welding involves heating of selected portions of the casing with attendant danger of deformation. Therefore, a welded-on extension must be tested by resorting to costly equipment and with additional loss in time. Furthermore, the welding itself is a costly and time-consuming operation.